Cleansing device for rock drills



June 28, 1932. G. w. HULSHIZER CLEANSING DEVICE FOR ROCK DRILLS FiledAug. 50, 1929 INVENTOR. deowlshi er BY I 2 HIS ATTORNEY Patented June28, 1932 -UNIT D STATES PATENT OFFICE GEORGE W. HULSHIZER, OFSTEWARTSVILLE, NEW JERSEY, ASSIGNOR TO INGERSOEL- RAND COMPANY, OFJERSEY CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY CLEANSING DEVICEFOR BOOK DRILLS Application filed August 30, 1929. Serial No. 889,419.

This invention relatesto rock drills, but more particularly to acleansing device for fluid actuated rock drills of the hammer type.

One object of the invention is 'toeflfect a thorough cleansing of thehole being drilled.

Another object is to control the flow of pressure fluid for this purposeby means of the hammer piston.

Still another object is to utilize a portion of the pressure fluid usedfor actuating the piston to augment the pressure of the cleansingliquid. I

Other objects will be in part obvious and in part pointed outhereinafter.

The figure in the accompanying drawing is a sectional elevation of arock drill con structed in accordance with the practice of theinvention.

Referring more particularly to the drawing, A designates a rock drillcomprising a cylinder B and front and back heads C and D respectively.These parts form the casing of the rock drill and may be securedtogether in any suitable manner, as for instance, by the usual sidebolts (not shown).

Within the cylinder B is a piston chamber E providedwith a reciprocatoryhammer piston F having a forwardly extending stem G in which are formedflutes H to interlocking-v lyen age ribs J of a chuckK in the fronthead' l The chuck K is rotatable in the front head C and carries" nearits forward end a chuck bushing L adapted to interlockingly engage aworking implement O which extends with its rearward or shank end'P intoa cavity Q'in the chuck K to receive the blows of the hammer piston F.

A suitable guideis provided for the stem G in the form of a frontcylinder washer R disposed in the front end of the cylinder B.

and havinga bore S through which thestem G slides. s

In the rearward end of the cylinder Bis an enlarged bore T- toaccommodate valve mechanism for distributing the pressure fluid to theends of the piston chamber to actuate the pistonF. The valve mechanism'comprises a valve chestU inv the form of two plates-W and X. The plateX is disposed adjacent the rearward end of the piston chamber E to forma closure therefore and the plate W issuper-imposed upon the plate X andhas a Valve chamber Y wherein is disposed a distributing valve Z of theoscillatory plate type.

' From one side of the valve chamber Y to the front end of the pistonchamber E leads an inlet passage 6 and the admission of pressure fluidfrom the valve chamber Y to the rearward end of the piston chamber E iseffected through an inlet passage 0 in the plate X. Both inlet passagesb and c are controlled by the valve Z, and the exhaust of pressure fluidfrom the piston chamber E is effected through a free exhaust port dcontrolled by the piston F.

Disposed in the bore T and rearwardly of the valve mechanism is therotation mechanism whereby the chuck K and thus also the workingimplement 0 maybe rotated through the medium of the piston F. Therotation mechanism comprises a ratchet ring 6 which is seated ontheplate W and a head 7 of a rifle bar 9 is adapted to rotate within theratchet ring 6. The head f carries the usual spring pressed pawls hadapted for cooperation with teeth j in the ratchet ring e to effeet astep by steprotary movement of the working implement. The rifle bar 9extends rotatably through the plates W and X and is provided with theusual flutes is to inter l ockingly engage a fluted rifle nut 0 threadedinto the rearward end of the piston F.

In-addition to forming a closure for the rearward end of the cylinder Bthe back head D also serves as a housing for a throttle valve pof therotary type having a central chamber 9 which maybe in constantcommunication with a source of pressure fluid supply. In the side ofthe, throttle valve p is a port 7' to register with a passage 8 in theback head D and opening into a supply reservoir t also in the back headD. Communication between the supply reservoir 25 and the valve chamber Yis afforded by supply passages u in the ratchet ring 2.

As is customary in devices of this character having rotation mechanismcomprising a rifle bar, the piston F is provided with a bore o to permitthe rifle bar to extend thereinto as well as such elements, as forinstance a water tube to, wherewith drills of this type are usuallyequipped for conveying cleansing liquid into a passage w in the workingimple ment.

Inasmuch that the tube to is of considerably smaller diameter than therifle bar the bore '21 is provided with a restricted portion y of onlysufficiently larger diameter than the tube '20 which it is intended toaccommodate to permit the free movement of the piston F on the tube w.The restricted portion 3 of the bore 4) may then act as a guide for theforward portion of the tube to to prevent extreme vibratory movement ofsaid tube. The opposite end of the tube 10 may be fixedly secured to theback head 1) in any convenient manner. v

' During the operation "of drills constructed in accordance with theforegoing description, aportion of the pressure fluid admitted into theforward end of the piston chamber E for driving the piston F rearwardlyflows I through the flutes H in the piston stem G when said flutes aredrawn into the. front end of the piston chamber. Such pressure fluidthen passes into the chuck cavity Q and from thence through the passageat in the working implement and into the drill hole.

In order to assure a rapid return mover nient of the piston it isessential that the flutes ,H be not placed in communication witli thepiston chamber too early during this stroke of the piston, otherwisethepressure of the fluid acting against the piston will be rest yi eh eIn view of these co iderations it is there: fore obvieus that no verygreat amount of pressure fluid may be supplied to the drill hole throughthese channels. The present invention contemplates augmentingtheordinary means fol",- flleimsing the drill hole. To his en th tu e w sprovid i h eek 2 ear t orw d e s at durin the for WMd st o e o t e pistn E the. r trict POL es. o e ere l o i to t e ame ransv t plan a the e 2o. pen com,- munication between the rearward enlarged 1-; portion of thebore a, and consequently the ea a d f e p t n. amber E, and the chuckcavity Q, V W

The neck a may be of suitable length so that pressnre fluid may flowthrough the re: stricted portion y of the bore throughout a considerableportion of the stroke of the pieton and the rearward end 2 of the neck ais preferably so located that it will be overrun by the correspondingend of the restricted portion y at the time or shortly after the pistonF is reversed for its forward stroke. The forward end 3 of the neck amay terminate at a point where it may again be overrun by the restrictedportion'y. of the bore '1) immediatelybefore the delivery of-the blow.

of the hammer piston against the working implement 0. Due to thisarrangement there is formed a portion l on the tube of substantially thesame diameter as the main body portion of the tube w which may cooperatewith the restricted portion y of the bore '0 to assure against whippingof the tube to at the instant of delivery of the blow of the hammerpiston to the working implement.

From the foregoing it will be readily apparent that in addition to thepressure fluid which escapes through the flutes H of the piston stem Gduring the rearward stroke of the piston a considerable volume ofpressure fluid may also be admitted into the passage as of the workingimplement Q during each forward stroke of the piston F. In this wayalternate aye o p ssure fluiden cle nsing liquid will flow through theworking implement and into the drill hole to remove the u i g he e om Byably prop rtio ing the neck a and the restricted portion y of the bore7; this desirable effect may be readil-y attained without in any wayaffecting the action of the hammer piston.

I claim:

1. In a fluid actuated rock drill, the combination of a cylinder and achuck, a hollow working implement extending into the chuck, a tube inthe cylinder for conveying cleansing liquid into the working implement,a neck on the tube, a hammer piston reciprocable in the cylinder, a borein the piston comprising a restricted portion through which pressurefluid flows to the working implement when said restricted portion liesin the same transverse plane as the neck, and means on said tube adaptedto be engaged by the restricted portion of the piston at the end of itsforward stroke.

2. In a fluid actuated rock drill, the combination of a cylinder and achuck, a hollow working implement extending into the chuck, a tube inthe cylinder for conveying cleansing liquid into the working iinplement,a neck on the tube, a piston reciprocable in the cylinder having a boreinto which pressure fluid flows from the rearward end of the cylinder, areduced portion in thebore cooperating with the neck to provide achannel for the flow of pressure fluid from the bore to the workingimplement, and means on said tube adapted to be engaged by therestricted portion of the piston at the end of it s forward stroke. i iI V 3. In a fluid actuated rock drill, the combination of a cylinder anda chuck, a hollow working implement extending into the. chuck, a tube inthe cylinder for conveying cleans ing liquid into the working implement,a neck near the forward extremity of the tube, a hammer pistonreciprocable in the cylinder, a bore in the piston in communication withthe rearward end of the cylinder to receive pressure fluid therefrom, arestricted portion in the front end of the bore cooperatin with a theneck to form a channel for the ow of pressure fluid from the bore to thechannel, and an extension on said tube adjacent the neck adapted to beengaged by the restricted portion of the piston at the end of itsforward stroke.

4. In a fluid actuated rock drill, a cylinder, a piston reoiprocable inthe cylinder and having a bore therein through which pressure fluidflows, a working implement positioned to receive blows delivered by saidpiston, a fluid connection for the working implement extending throughthe bore of the piston, a neck on said fluid connection 7 cooperatingwith the bore of the piston during its forward stroke to provide passagefor pressure fluid from the piston bore to the working implement, and anextension on said connection forwardly of the neck and adapted to beengaged by the bore of the piston at the end of its forward stroke tosupport said connection during delivery of the piston blow.

5. In a fluid actuated rock drill, a cylinder having a hollow pistonreciprocable therein, a working implement positioned to receive blowsdelivered by said piston, a fluid conduit extending through a bore inthe piston to. the working implement, said conduit having a reducedexternal diameter near the forward end thereof to permit passage ofpressure fluid through the bore of the piston, and a portion of normaldiameter forwardly of said reduced portion to coact with the piston atthe moment of impact with the working implement.

In testimony whereof I have signed this specification.

GEORGE W. HULSHIZER.

